1
|
Wu T, Zhang Z, Li T, Dong X, Wu D, Zhu L, Xu K, Zhang Y. The type III secretion system facilitates systemic infections of Pseudomonas aeruginosa in the clinic. Microbiol Spectr 2024; 12:e0222423. [PMID: 38088541 PMCID: PMC10783026 DOI: 10.1128/spectrum.02224-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 11/14/2023] [Indexed: 01/13/2024] Open
Abstract
IMPORTANCE The identification of decisive virulence-associated genes in highly pathogenic P. aeruginosa isolates in the clinic is essential for diagnosis and the start of appropriate treatment. Over the past decades, P. aeruginosa ST463 has spread rapidly in East China and is highly resistant to β-lactams. Given the poor clinical outcome caused by this phenotype, detailed information regarding its decisive virulence genes and factors affecting virulence expression needs to be deciphered. Here, we demonstrate that the T3SS effector ExoU has toxic effects on mammalian cells and is required for virulence in the murine bloodstream infection model. Moreover, a functional downstream SpcU is required for ExoU secretion and cytotoxicity. This work highlights the potential role of ExoU in the pathogenesis of disease and provides a new perspective for further research on the development of new antimicrobials with antivirulence ability.
Collapse
Affiliation(s)
- Tiantian Wu
- Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhenchuan Zhang
- Research Center for Healthcare Data Science, Zhejiang Lab, Hangzhou, China
| | - Tong Li
- Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xu Dong
- Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Dan Wu
- Research and Service Center, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
- College of Food and Health, Zhejiang A&F University, Lin'an, Hangzhou, China
| | - Lixia Zhu
- Department of Hematology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Kaijin Xu
- Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ying Zhang
- Department of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Jinan Microecological Biomedicine Shandong Laboratory, Jinan, China
| |
Collapse
|
2
|
Xiao S, Liang X, Han L, Zhao S. Incidence, antimicrobial resistance and mortality of Pseudomonas aeruginosa bloodstream infections among hospitalized patients in China: a retrospective observational multicenter cohort study from 2017 to 2021. Front Public Health 2024; 11:1294141. [PMID: 38249405 PMCID: PMC10797092 DOI: 10.3389/fpubh.2023.1294141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 12/13/2023] [Indexed: 01/23/2024] Open
Abstract
Background Pseudomonas aeruginosa (P. aeruginosa) accounts for high antimicrobial resistance and mortality rates of bloodstream infections (BSIs). We aim to investigate incidence, antimicrobial resistance and risk factors for mortality of P. aeruginosa BSIs among inpatients. Methods A retrospective cohort study were conducted at two tertiary hospitals in 2017-2021. Medical and laboratory records of all inpatients diagnosed with P. aeruginosa BSIs were reviewed. A generalized linear mixed model was used to identify risk factors for mortality. Results A total of 285 patients with P. aeruginosa BSIs were identified. Incidence of P. aeruginosa BSIs fluctuated between 2.37 and 3.51 per 100,000 patient-days over the study period. Out of 285 P. aeruginosa isolates, 97 (34.04%) were carbapenem-resistant (CR) and 75 (26.32%) were multidrug-resistant (MDR). These isolates showed low resistance to aminoglycosides (9.51-11.62%), broad-spectrum cephalosporins (17.19-17.61%), fluoroquinolones (17.25-19.43%), and polymyxin B (1.69%). The crude 30-day mortality rate was 17.89% (51/285). Healthcare costs of patients with MDR/CR isolates were significantly higher than those of patients with non-MDR/CR isolates (P < 0.001/=0.002). Inappropriate definitive therapy [adjusted odds ratio (aOR) 4.47, 95% confidence interval (95% CI) 1.35-14.77; P = 0.014], ICU stay (aOR 2.89, 95% CI: 1.26-6.63; P = 0.012) and corticosteroids use (aOR 2.89, 95% CI: 1.31-6.41; P = 0.009) were independently associated with 30-day mortality. Conclusion Incidence of P. aeruginosa BSIs showed an upward trend during 2017-2020 but dropped in 2021. MDR/CR P. aeruginosa BSIs are associated with higher healthcare costs. Awareness is required that patients with inappropriate definitive antimicrobial therapy, ICU stay and corticosteroids use are at higher risk of death from P. aeruginosa BSIs.
Collapse
Affiliation(s)
- Shuzhen Xiao
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xianghui Liang
- Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Lizhong Han
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shengyuan Zhao
- Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, Hunan, China
| |
Collapse
|
3
|
Chen J, Huang H, Liu C, Fu YQ. Risk factors for mortality in pseudomonas aeruginosa bacteremia in children. Pediatr Neonatol 2024; 65:31-37. [PMID: 37517970 DOI: 10.1016/j.pedneo.2023.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 02/04/2023] [Accepted: 03/02/2023] [Indexed: 08/01/2023] Open
Abstract
BACKGROUND The incidence of Pseudomonas aeruginosa (P. aeruginosa) bacteremia in children ranks third to fourth among gram-negative bacilli bacteremia, which is one of the main conditional pathogens in hospitals. This study aimed to identify the clinical characteristics and risk factors of 60-day in-hospital mortality in children with P. aeruginosa bacteremia. METHODS This retrospective study was conducted in a tertiary pediatric hospital between January 2015 and December 2021 including children with P. aeruginosa bacteremia. Kaplan-Meier survival analysis was used to investigate the time-to-event outcomes. Logistic regression was used to explore the independent risk factors for 60-day mortality. RESULTS Overall, 75 patients with P. aeruginosa bacteremia episodes were identified. Immunosuppression (52%) was the most common underlying condition, followed by neutropenia (50.7%) and hematological malignancies (48%). Among 75 patients with P. aeruginosa bacteremia, 25 (33.3%) had septic shock, 30 (40%) had respiratory failure, and 20 (26.7%) had liver function impairment. The 60-day in-hospital mortality was 17.3%. In multivariate analysis, independent risk factors for 60-day mortality were respiratory failure [odds ratio (OR) 39.329; 95% CI:3.212-481.48, P = 0.004) and liver function impairment (OR 17.925; 95% CI:2.909-139.178, P = 0.002). CONCLUSION Respiratory failure and liver function impairment seem to be related to poor prognosis in children with P. aeruginosa bacteremia.
Collapse
Affiliation(s)
- Jian Chen
- Department of Critical Care Medicine, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Haixin Huang
- Department of Critical Care Medicine, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Chengjun Liu
- Department of Critical Care Medicine, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Yue-Qiang Fu
- Department of Critical Care Medicine, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China.
| |
Collapse
|
4
|
Bogiel T, Depka D, Rzepka M, Mikucka A. Decoding Genetic Features and Antimicrobial Susceptibility of Pseudomonas aeruginosa Strains Isolated from Bloodstream Infections. Int J Mol Sci 2022; 23:ijms23169208. [PMID: 36012468 PMCID: PMC9409454 DOI: 10.3390/ijms23169208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/11/2022] [Accepted: 08/15/2022] [Indexed: 11/16/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative rod and an etiological factor of opportunistic infections. The infections of this etiology appear mostly among hospitalized patients and are relatively hard to treat due to widespread antimicrobial resistance. Many virulence factors are involved in the pathogenesis of P. aeruginosa infection, the coexistence of which have a significant impact on the course of an infection with a particular localization. The aim of this study was to assess the antimicrobial susceptibility profiles and the frequency of genes encoding selected virulence factors in clinical P. aeruginosa strains isolated from bloodstream infections (BSIs). The following genes encoding virulence factors of enzymatic activity were assessed: lasB, plC H, plC N, nan1, nan2, aprA and phzM. The frequency of the genes encoding the type III secretion system effector proteins (exoU and exoS) and the genes encoding pilin structural subunits (pilA and pilB) were also investigated. The occurrence of virulence-factor genes was assessed using polymerase chain reactions, each in a separate reaction. Seventy-one P. aeruginosa strains, isolated from blood samples of patients with confirmed bacteremia hospitalized at the University Hospital No. 1 of Dr. Antoni Jurasz in Bydgoszcz, Poland, were included in the study. All the investigated strains were susceptible to colistin, while the majority of the strains presented resistance to ticarcillin/clavulanate (71.8%), piperacillin (60.6 %), imipenem (57.7%) and piperacillin/tazobactam (52.1%). The presence of the lasB and plC H genes was noted in all the tested strains, while the plC N, nan2, aprA, phzM and nan1 genes were identified in 68 (95.8%), 66 (93.0%), 63 (88.7%), 55 (77.5%) and 34 (47.9%) isolates, respectively. In 44 (62.0%) and 41 (57.7%) strains, the presence of the exoU and exoS genes was confirmed, while the pilA and pilB genes were noted only in 14 (19.7%) and 3 (4.2%) isolates, respectively. This may be due to the diverse roles of these proteins in the development and maintenance of BSIs. Statistically significant correlations were observed between particular gene pairs’ coexistence (e.g., alkaline protease and neuraminidase 2). Altogether, twenty-seven distinctive genotypes were observed among the studied strains, indicating the vast variety of genetic compositions of P. aeruginosa strains causing BSIs.
Collapse
|
5
|
O'Donnell JN, Putra V, Belfiore GM, Maring BL, Young K, Lodise TP. In vitro activity of imipenem/relebactam plus aztreonam against metallo-β-lactamase producing, OprD-deficient Pseudomonas aeruginosa with varying levels of Pseudomonas-derived cephalosporinase production. Int J Antimicrob Agents 2022; 59:106595. [PMID: 35483625 DOI: 10.1016/j.ijantimicag.2022.106595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 03/07/2022] [Accepted: 04/17/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND Limited treatment options exist for metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa infections. Imipenem/relebactam plus aztreonam may be an option. METHODS Ten OprD(-) P. aeruginosa isolates (3 parent strains; 7 MBL-producers) were evaluated using checkerboard methodology and Fractional Inhibitory Concentration Index (FICI). Isolates exhibiting synergy in checkerboard studies (FICI ≤0.5) were evaluated using 24-hour static concentration time-kill. Bacteria in late log-phase growth were diluted to 1 × 106 cfu/mL and incubated at 37°C for 24 hours. Samples were drawn at 0, 2, 4, 6 and 24 hours. Physiologic fCmax, fCss,avg and fCmin of imipenem (26.7, 5.6, 0.5 mg/L), relebactam (13.1, 4, 0.8 mg/L) and aztreonam (62, 29, 8 mg/L) were used. Synergy in time-kill studies was defined as >2 log10 cfu/mL reduction compared to the most active individual agent. RESULTS Synergy was observed in five isolates in checkerboard studies, including three of seven MBL-producing isolates. Isolates which were OprD(-) and harboured inducible Pseudomonas-derived cephalosporinases (PDCs) did not show synergy as defined by FICI, however aztreonam MICs were significantly reduced with the combination. In time-kill studies, ATM alone was as active as combination regimens for MBL-producing isolates with deleted or inducible PDC production. For strains exhibiting constitutive PDC production, I/R plus ATM was synergistic at fCss,avg concentrations but exhibited similar activity to ATM at fCmin and fCmax concentrations. CONCLUSIONS Imipenem/relebactam plus aztreonam appears to exhibit synergy for some MBL-producing P. aeruginosa at physiologic concentrations. Further study of the effect of dynamic concentrations is needed to understand fully the utility of this combination.
Collapse
Affiliation(s)
- J Nicholas O'Donnell
- Assistant Professor of Pharmacy Practice, Department of Pharmacy Practice, Albany College of Pharmacy and Health Sciences, Albany, NY, USA.
| | - Vibert Putra
- Graduate Research Assistant, Department of Basic and Clinical Sciences, Albany College of Pharmacy and Health Sciences, Albany, NY, USA
| | - Gina M Belfiore
- PharmD Candidate, Department of Pharmacy Practice, Albany College of Pharmacy and Health Sciences, Albany, NY, USA
| | - Brittney L Maring
- Research Assistant, Department of Pharmacy Practice, Albany College of Pharmacy and Health Sciences, Albany, NY, USA
| | - Katherine Young
- Senior Principal Scientist, Merck & Co., Inc., Kenilworth, NJ, USA
| | - Thomas P Lodise
- Professor of Pharmacy Practice, Department of Pharmacy Practice, Albany College of Pharmacy and Health Sciences, Albany, NY, USA
| |
Collapse
|
6
|
How to Manage Pseudomonas aeruginosa Infections. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:425-445. [DOI: 10.1007/978-3-031-08491-1_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
7
|
Morin CD, Déziel E, Gauthier J, Levesque RC, Lau GW. An Organ System-Based Synopsis of Pseudomonas aeruginosa Virulence. Virulence 2021; 12:1469-1507. [PMID: 34180343 PMCID: PMC8237970 DOI: 10.1080/21505594.2021.1926408] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Driven in part by its metabolic versatility, high intrinsic antibiotic resistance, and a large repertoire of virulence factors, Pseudomonas aeruginosa is expertly adapted to thrive in a wide variety of environments, and in the process, making it a notorious opportunistic pathogen. Apart from the extensively studied chronic infection in the lungs of people with cystic fibrosis (CF), P. aeruginosa also causes multiple serious infections encompassing essentially all organs of the human body, among others, lung infection in patients with chronic obstructive pulmonary disease, primary ciliary dyskinesia and ventilator-associated pneumonia; bacteremia and sepsis; soft tissue infection in burns, open wounds and postsurgery patients; urinary tract infection; diabetic foot ulcers; chronic suppurative otitis media and otitis externa; and keratitis associated with extended contact lens use. Although well characterized in the context of CF, pathogenic processes mediated by various P. aeruginosa virulence factors in other organ systems remain poorly understood. In this review, we use an organ system-based approach to provide a synopsis of disease mechanisms exerted by P. aeruginosa virulence determinants that contribute to its success as a versatile pathogen.
Collapse
Affiliation(s)
- Charles D Morin
- Centre Armand-Frappier Santé Biotechnologie, Institut National De La Recherche Scientifique (INRS), Laval, Quebec, Canada
| | - Eric Déziel
- Centre Armand-Frappier Santé Biotechnologie, Institut National De La Recherche Scientifique (INRS), Laval, Quebec, Canada
| | - Jeff Gauthier
- Département De Microbiologie-infectiologie Et Immunologie, Institut De Biologie Intégrative Et Des Systèmes (IBIS), Université Laval, Québec City, Quebec, Canada
| | - Roger C Levesque
- Département De Microbiologie-infectiologie Et Immunologie, Institut De Biologie Intégrative Et Des Systèmes (IBIS), Université Laval, Québec City, Quebec, Canada
| | - Gee W Lau
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL, US
| |
Collapse
|
8
|
Sherrard LJ, Wee BA, Duplancic C, Ramsay KA, Dave KA, Ballard E, Wainwright CE, Grimwood K, Sidjabat HE, Whiley DM, Beatson SA, Kidd TJ, Bell SC. Emergence and impact of oprD mutations in Pseudomonas aeruginosa strains in cystic fibrosis. J Cyst Fibros 2021; 21:e35-e43. [PMID: 33775602 DOI: 10.1016/j.jcf.2021.03.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 03/01/2021] [Accepted: 03/02/2021] [Indexed: 12/31/2022]
Abstract
BACKGROUND Antimicrobial resistance in cystic fibrosis (CF) Pseudomonas aeruginosa airway infection is complex and often attributed to chromosomal mutations. How these mutations emerge in specific strains or whether particular gene mutations are clinically informative is unclear. This study focused on oprD, which encodes an outer membrane porin associated with carbapenem resistance when it is downregulated or inactivated. AIM Determine how mutations in oprD emerge in two prevalent Australian shared CF strains of P. aeruginosa and their clinical relevance. METHODS The two most common shared CF strains in Queensland were investigated using whole genome sequencing and their oprD sequences and antimicrobial resistance phenotypes were established. P. aeruginosa mutants with the most common oprD variants were constructed and characterised. Clinical variables were compared between people with or without evidence of infection with strains harbouring these variants. RESULTS Frequently found nonsense mutations arising from a 1-base pair substitution in oprD evolved independently in three sub-lineages, and are likely major contributors to the reduced carbapenem susceptibility observed in the clinical isolates. Lower baseline FEV1 %predicted was identified as a risk factor for infection with a sub-lineage (odds ratio=0.97; 95% confidence interval 0.96-0.99; p<0.001). However, acquiring these sub-lineage strains did not confer an accelerated decline in FEV1 nor increase the risk of death/lung transplantation. CONCLUSIONS Sub-lineages harbouring specific mutations in oprD have emerged and persisted in the shared strain populations. Infection with the sub-lineages was more likely in people with lower lung function, but this was not predictive of a worse clinical trajectory.
Collapse
Affiliation(s)
| | - Bryan A Wee
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Australia
| | | | - Kay A Ramsay
- QIMR Berghofer Medical Research Institute, Brisbane, Australia; Faculty of Medicine, The University of Queensland, Brisbane, Australia
| | - Keyur A Dave
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Emma Ballard
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Claire E Wainwright
- Faculty of Medicine, The University of Queensland, Brisbane, Australia; Department of Respiratory and Sleep Medicine, Queensland Children's Hospital, Brisbane, Australia
| | - Keith Grimwood
- School of Medicine and Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia; Departments of Infectious Diseases and Paediatrics, Gold Coast Health, Gold Coast, Australia
| | - Hanna E Sidjabat
- UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia
| | - David M Whiley
- UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia; Pathology Queensland Central Laboratory, Brisbane, Australia
| | - Scott A Beatson
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Australia; Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Australia; Australian Centre for Ecogenomics, The University of Queensland, Brisbane, Australia
| | - Timothy J Kidd
- QIMR Berghofer Medical Research Institute, Brisbane, Australia; School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Australia.
| | - Scott C Bell
- QIMR Berghofer Medical Research Institute, Brisbane, Australia; Faculty of Medicine, The University of Queensland, Brisbane, Australia; Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Australia; Department of Thoracic Medicine, The Prince Charles Hospital, Brisbane, Australia.
| |
Collapse
|
9
|
Yoon EJ, Jeong SH. Mobile Carbapenemase Genes in Pseudomonas aeruginosa. Front Microbiol 2021; 12:614058. [PMID: 33679638 PMCID: PMC7930500 DOI: 10.3389/fmicb.2021.614058] [Citation(s) in RCA: 82] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/04/2021] [Indexed: 02/06/2023] Open
Abstract
Carbapenem-resistant Pseudomonas aeruginosa is one of the major concerns in clinical settings impelling a great challenge to antimicrobial therapy for patients with infections caused by the pathogen. While membrane permeability, together with derepression of the intrinsic beta-lactamase gene, is the global prevailing mechanism of carbapenem resistance in P. aeruginosa, the acquired genes for carbapenemases need special attention because horizontal gene transfer through mobile genetic elements, such as integrons, transposons, plasmids, and integrative and conjugative elements, could accelerate the dissemination of the carbapenem-resistant P. aeruginosa. This review aimed to illustrate epidemiologically the carbapenem resistance in P. aeruginosa, including the resistance rates worldwide and the carbapenemase-encoding genes along with the mobile genetic elements responsible for the horizontal dissemination of the drug resistance determinants. Moreover, the modular mobile elements including the carbapenemase-encoding gene, also known as the P. aeruginosa resistance islands, are scrutinized mostly for their structures.
Collapse
Affiliation(s)
- Eun-Jeong Yoon
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
| | - Seok Hoon Jeong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
| |
Collapse
|
10
|
Xu Y, Zheng X, Zeng W, Chen T, Liao W, Qian J, Lin J, Zhou C, Tian X, Cao J, Zhou T. Mechanisms of Heteroresistance and Resistance to Imipenem in Pseudomonas aeruginosa. Infect Drug Resist 2020; 13:1419-1428. [PMID: 32523360 PMCID: PMC7234976 DOI: 10.2147/idr.s249475] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/21/2020] [Indexed: 11/23/2022] Open
Abstract
Background Heteroresistance is a phenomenon that occurs in all bacteria and can cause treatment failure. Yet, the exact mechanisms responsible for heteroresistance still remain unknown. The following study investigated the mechanisms of imipenem-heteroresistance and -resistance in Pseudomonas aeruginosa clinical isolates from Wenzhou, China. Methods Imipenem resistance was detected by the agar dilution method; heteroresistance was determined by population analysis profiles. Biofilm formation assay and modified carbapenem inactivation methods were also performed. Polymerase chain reaction (PCR) was conducted to detect oprD, and quantitative real-time PCR was used to determine expression levels of oprD, ampC and four efflux pump coding genes (mexB, mexD, mexE and mexY). Results Six imipenem-heteroresistant and -resistant P. aeruginosa isolates were selected respectively. Deficient oprD was detected in all resistant isolates and two heteroresistant isolates. No strains produced carbapenemases. Expression levels of oprD were down-regulated in heteroresistant isolates. Transcription levels of the mexE and mexY were significantly increased in all heterogeneous subpopulations compared with their respective native ones. Compared with the susceptible group, increased mean relative expression levels of mexE and mexY or the decreased mean relative expression levels of oprD were observed in the resistant group (P < 0.05), whereas transcription levels of the mexB and mexD remained unchanged. Conclusion Down-regulation of oprD contributed to the resistance and heteroresistance of imipenem in our P. aeruginosa clinical isolates. In addition, the marginal up-regulation of efflux systems may indirectly affect imipenem resistance. Contrarily, defective oprD was less common in our experimental heteroresistant strains than resistant strains.
Collapse
Affiliation(s)
- Ye Xu
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Xiangkuo Zheng
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Weiliang Zeng
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Tao Chen
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Wenli Liao
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Jiao Qian
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Jie Lin
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Cui Zhou
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Xuebin Tian
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Jianming Cao
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| | - Tieli Zhou
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China
| |
Collapse
|
11
|
Risk Factors for Mortality among Patients with Pseudomonas aeruginosa Bloodstream Infections: What Is the Influence of XDR Phenotype on Outcomes? J Clin Med 2020; 9:jcm9020514. [PMID: 32074947 PMCID: PMC7074151 DOI: 10.3390/jcm9020514] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 02/06/2020] [Accepted: 02/08/2020] [Indexed: 12/14/2022] Open
Abstract
This study aimed to assess the impact of extensively drug-resistant (XDR) phenotype on mortality in Pseudomonas aeruginosa bacteremia. A retrospective cohort study was performed in a tertiary hospital from January 2000 to December 2018. All consecutive prospectively recorded P. aeruginosa bacteremia in adult patients were assessed. In this study, 382 patients were included, of which 122 (31.9%) due to XDR P. aeruginosa. Independent factors associated with 14-day mortality were as follows: high-risk source of bacteremia (hazard ratio (HR) 3.07, 95% confidence interval (CI), 1.73–5.46), septic shock (HR 1.75, 95% CI, 1.12–2.75), and higher Pitt scores (one-point increments; HR 1.25, 95% CI, 1.12–1.38). Otherwise, the appropriateness of definitive antibiotic therapy was a protective factor (HR 0.39, 95% CI, 0.24–0.62). The same variables were also associated with 30-day mortality. XDR phenotype was not associated with 14- or 30-day mortality. In a subanalysis considering only high-risk source cases, combined antimicrobial therapy was independently associated with 14-day favorable outcome (HR 0.56, 95% CI, 0.33–0.93). In conclusion, XDR phenotype was not associated with poor prognosis in patients with P. aeruginosa bacteremia in our cohort. However, source of infection, clinical severity, and inappropriate definitive antibiotic therapy were risk factors for mortality. Combined antimicrobial therapy should be considered for high-risk sources.
Collapse
|